Психофармакология и биологическая наркология, Том 5, № 2 (2005)

advertisement your ad here

Psychosocial Stress Versus Physical Environment — Increased Sensor Responsiveness and Lability of the Autonomous Nervous System in Patients With Idiopathic Chronic Pain and Environmental Intolerance

E. Lyskov, K. Hansson Mild, S. Medvedev


Proceedings of the 9th International Multidisciplinary Conference «Stress and Behavior» Saint-Petersburg, Russia, 16–19 May 2005.

Recent data of clinical and psycho-physiological studies indicated rather consistent pattern of modest (but significant on the group level) difference in stress related physiological indicies between persons with idiopathic chronic pain and environmental intolerance. Although these pathological forms are characterized by a wide spectrum of non specific somatic and neurasthenic symptoms, sometimes very different in dynamics and essence — increased sensor responsiveness and engagement of the autonomous nervous system are rather common pathophysiological profile in these patients. The autonomic regulation showed distinctive trend towards increased tone of the sympathetic system even in so-called baseline (rest) conditions. Heart rate variability in time and frequency domain as well as spontaneous electrodermal activity were shown to be sensitive parameters in this respect. Surprisingly, there have been no clear relationships between degree of the sympathetic overtone and severity of symptoms. Description of reactivity was more complicated, since high individual variability in particular tests and lack of commonly accepted normatives for majority of functional tests dealing with visual, audio, somato-sensory stimulation, cognitive efforts and emotional loads, low-level physical loads. Nevertheless, with certain simplification one may state that patients with environmental intolerance and some forms of chronic pain have demonstrated increased sensitivity to flickering light, irritated noise, vibration. Facilitated reactions were typical for CNS (EEG, evoked potentials, sEMG) and ANS (heart rate variability, skin sympathetic response, local blood flow) parameters. No specific trends in reactions to mental tasks, exposure to magnetic fields or chemicals have been observed. Obtained physiological data indicate that imbalance of the autonomic regulation and increased responsiveness to sensor stimulation play essential role in the development of idiopathic pain and environmental intolerance; we also assume an incidence of the common, somatic» component of the pathogenesis and important role of cortical sensor processing and suprasegmental levels of ANS regulation.

This work is licensed under a Creative Commons Attribution 3.0 Unported License. Online ISSN 2070–5670Print ISSN 1606–8181CD ISSN 1999–7337